Nanotechnology in the life sciences
A FRONTIS LECTURE SERIES
organized by
Pieter Stroeve
Department of Chemical Engineering and
Materials Science
University of California, Davis
Davis, CA 95616, USA
Nanotechnology in the life sciences
February 13
February 20
February 27
13:30
14:30
13:30
14:30
13:30
14:30
Friday, March 5
13:30
14:30
Friday, March 12 13:30
14:30
Pieter Stroeve-Size, measurement and sensing
Mieke Kleijn (WUR)- Surface forces using AFM
Pieter Stroeve- (Bio)materials
Ernst Sudholter (WUR)- Hybrid organic
semiconductor FETs
Pieter Stroeve- Self-assembly of molecular
structures
Richard Schasfoort (U Twente)- Surface modification and
microfabrication strategies
Pieter Stroeve- Nanotechnology and the environment
Keurentje (TU Eindhoven)- Micellar systems for nanoscale
engineering of reaction and separation processes
Pieter Stroeve- Life sciences and medicine
Ton Visser (WUR)- Single-molecule fluorescence in
microfluidic devices
Nanotechnology in the life sciences
TOPICS
• Biosensing
• Microarrays: genes and proteins
• Nanoparticle complexes of DNA and peptides
• Drug encapsulation and delivery
• Molecular machines and devices
What do we want to sense?
• toxins in food
• pollutants in air and water
• bioprocess monitoring
• viruses
• bacteria
• metal ions
• biochemicals
• bacterial activity
• intracellular
Biological recognition elements for sensors
• Enzymes
-transformation of analyte into sensor detectable product
-inhibition of enzyme by analyte
-detectable characteristic of change of enzyme by analyte
• Antibody-antigens
-high affinity binding with tracer to generate a signal
• DNA-ligand binding
• Biomimetic sensors
-engineered molecules (single chain antibody fragment)
-supported lipid bilayers
-molecularly imprinted polymers
•Whole cells or cellular structures
-pollutant dependent inhibition of cell respiration
-pollution dependent increase in cell respiration
-membrane transport proteins
-neuroreceptor proteins produce signal through ion channels
Typical sensing techniques for
biosensors and biochips
• Fluorescence
• SPR Surface plasmon resonance
• Ellipsometry
• SHG Second harmonic generation
• QCM Quartz crystal microbalance
• SAW Surface acoustic wave
• Impedance spectroscopy
• SPM Scanning probe microscopy
• Electrochemical
Surface immobilization of molecules
for biosensing
Microfluidics based biochip for sensing
T. Vo-Dingh et al., Sensors and Actuators B, 2001
Fiber-optic cholesterol sensor
The enzyme cholesterol oxidase converts cholesterol and oxygen to
cholestenone and peroxide. The change in oxygen is sensed by the
decacyclene fluorescence. B. Kuswandi et al., Analyst, 2001
SEM of optical fiber
Tip size of optical fibers can be as small as 40 nm.
T. Vo-Dingh et al., Sensors and Actuators B, 2001
Optical system for intracellular
measurement
T. Vo-Dingh et al., Sensors and Actuators B, 2001
Optical fiber microarray
Fiber bundle is 1 mm2 and contains 50,000 individual fibers.
J. R. Epstein and D. R. Walt, Chem. Soc. Rev., 2003
pH sensing by optical fiber microarray:
intensity proportional to pH value
J. R. Epstein and D. R. Walt, Chem. Soc. Rev., 2003
Nanotechnology in the life sciences
• Biosensing
• Î Microarrays: genes and proteins
• Nanoparticle complexes of DNA and peptides
• Drug encapsulation and delivery
• Molecular machines and devices
Microarrays or gene chips
• DNA microarrays can track thousands of molecular
reactions in parallel on a wafer smaller than a microscope
slide. Chips can be designed to detect specific genes or
measure gene activity in tissue samples.
• Microarrays are being studied as diagnostic tools.
• Protein arrays are being developed and have great
promise as diagnostic devices for proteomics- the study of
networks of proteins in cells and tissues. However,
proteins are more complex than genes and more difficult
to study.
• Identification of proteins and the 3-D structures allows
one to find sites where proteins are most vulnerable to
drugs.
Microarrays
Microarray with single-stranded DNA representing thousands of different
genes, each assigned to a specific spots on a 2.5 by 2.5 cm device. Each spot
includes thousands of to millions of copies of a DNA strand.
Microarrays for gene diagnostics
S. H. Friend and R.B. Stoughton, Sci. Am., 2002
Protein arrays for diagnostics
S. H. Friend and R.B. Stoughton, Sci. Am., 2002
Nanotechnology in the life sciences
• Biosensing
• Microarrays: genes and proteins
• Î Nanoparticle complexes of DNA and peptides
• Drug encapsulation and delivery
• Molecular machines and devices
Nanoconstructions of DNA and DNAnanoparticle complexes
1) DNA molecule; 2) DNA-nanoparticle complexes based on Au-thiol
binding; 3) nanoparticle labeling for biochips; 4) labeling of single
molecules; 5) devices, e.g. nanoelectronics.
A. Csaki et al., Single Mol., 2003
Nanoparticles as labels for DNA
a) nanoparticle (arrows) and DNA fragment (arrow
head); b) nanoparticle with complete DNA; c) zoom of b).
A. Csaki et al., Single Mol., 2002
Nanoparticles for DNA-chip labeling
a) optical reflection picture of nanoparticle-labeled DNA chip;
b) AFM zoom of one square of a); c-e) concentration-dependence of
surface coverage (height range 50 nm, scan size 2 x 2 μm)
A. Csaki et al., Single Mol., 2002
Metal nanocrystal-coupled DNA as a
switch
S. Zhang, Nature Biotechnology, 2003
Lipid, peptide and protein scaffolds
a) Nanoparticles coated on left-handed lipid tubules. b) silver ions fill a tubule from a
peptide. The silver can form a wire after removal of the peptide scaffold. c) yeast protein
forms bridges to gold electrodes. The fibers can pass electric current. d) electronic/peptide
device by binding peptide to GaAs pattern on SiO2 .
Zhang, Nature Biotechnology, 2003
Nanotechnology in the life sciences
• Biosensing
• Microarrays: genes and proteins
• Nanoparticle complexes of DNA and peptides
• Î Drug encapsulation and delivery
• Molecular machines and devices
Drug encapsulation and delivery with
nanoparticles: vehicles for delivery
• coated solid particles
• vesicles
• liposomes
• micelles
• polymers
• solid lipid nanoparticles
A paradigm for nanoparticle delivery for
controlled release of drugs or genes or for
tissue and cell imaging
S.A. Wickline and G. M. Lanza, J. Cell. Biochem., 2002
Intracellular trafficking of nanoparticles
Nanoparticles eventually act as intracellular reservoirs for sustained
release of encapsulated therapeutic agent.
V. Panyam and V. Labhasetwar, Adv. Drug Deliv. Rev., 2003
TEM micrograph of PLGA nano
particles in cytoplasm of vascular
smooth muscle cells
PLGA poly(D,L-lactide-co-glycolide) is a biodegradable polymer.
Bar is 250 nm. V. Panyam and V. Labhasetwar, Adv. Drug Deliv. Rev., 2003
Tissue targeting of nanoparticles
Cross section of pig coronary artery infused with rhodamine B
containing PLGA nanoparticles. Intense fluorescence indicates
deposition of nanoparticles in the arterial wall. L=lumen,
NP=nanoparticles, A= adventitia.
L.labhasetwar et al., Adv. Drug Deliv. Rev., 1997
Tissue targeting with surface modification:
U-86 drug levels in an arterial vivo model
EP=epoxide, HP=heparin, PL=lipofectin, CYNO=cyanoacrylate, FERR=ferritin,
FN=fibronectin, DEAE=DEAE-dextran, DMAB=didodecyldimethyl ammonium
bromide, FG=fibrinogen, and LP=L-α-phosphatidylethanolamine.
V. Labhasetwar et al., J. Pharm. Sci., 1998
Layer-by-layer polyelectrolyte
coating of nanoparticles
M. Schonhoff, Curr. Op. Coll. Surf. Sci., 2003
Block copolymer micelles for gene therapy
Transfection of plasmid DNA using diblock copolymer. DNA is released
inside the cytosol and appears in the nucleus to express a desired protein.
Forster and M. Konrad, J. Mater. Chem., 2003
Pluronic (triblock copolymer) grid and
transport into cells: polymer structure
E.V. Batrakova et al., J. Pharm. Exp. Therapeutics, 2003
Nanostructured lipid carriers
Phase separation process during cooling in solid lipid nanoparticle
(SLN) production leading to a drug enriched shell and consequently
leads to a drug burst release upon use. R.H. Muller et al., Int. J. Pharmaceut., 2002
Cell microencapsulation in polymer matrix
surrounded by semipermeable membrane
G. Orive et al., Trends Pharmacol. Sci., 2003
Nanotechnology in the life sciences
• Biosensing
• Microarrays: genes and proteins
• Nanoparticle complexes of DNA and peptides
• Drug encapsulation and delivery
• Î Molecular machines and devices
Machines and molecular machines
S. Zhang, Nature Biotechnology, 2003
Motor protein in-vivo
A vesicle-carrying kinesin bound to a microtubule
Hirokawa, Science, 1998; Hess and Vogel, Rev. Mol. Biotechnology 2001
Motor protein: myosin on actin filament
Simplified cartoon of the myosin power stroke.
B.S. Lee et al., Biomed. Microdevices, 2003
Molecular machines in-vitro
Hess and Vogel, Rev. Mol. Biotechnology 2001
Molecular machines and devices: what can
we learn from biology and what machines
and devices can we create that have useful
biological functions?
• Power generators
• Locomotion systems
• Sensor systems
• Switches
• Control systems
• Assembly systems
• Disposal systems
Nanotechnology challenges in the life
sciences
- Making materials and products bottom-up by building them up from
atoms and molecules.
- Molecularly engineering of new molecules for bottom-up structures
- Understanding the forces that stabilize and maintain
supermacromolecular structures.
- Developing nanocomposite materials that are stronger than steel, but a
fraction of the weight (e.g. for implantable materials)
- Using gene and drug delivery to detect and treat cancerous cells or
diseases
- Developing nanosensors for pollutants, viruses, toxins, bacteria, cellular
activity, monitoring bioprocesses, etc.
- Removing toxins to promote a cleaner environment.
- Developing molecular machines for biological functions.